Pressurized liquid stream with dissolved gas

ABSTRACT

A system and method of injecting a gas enriched and/or emulsified first liquid into a second liquid is disclosed. The injection can cause generation of a high density of bubbles having a mean diameter of a selected size. The mean diameter of the bubbles can be selected and varied based on the characteristics of the injection system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/959,200 filed on Aug. 5, 2013, which is a divisional of U.S.application Ser. No. 12/795,362 filed Jun. 7, 2010, now U.S. Pat. No.8,500,104 issued on Aug. 6, 2013. The disclosures of the aboveapplications are incorporated herein by reference.

FIELD

The present disclosure relates to pressurizing a liquid, andparticularly to pressurizing an aqueous fluid with a gas to dissolve gasin the liquid for generating a stream of the liquid including smallbubbles.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

In providing flow of a liquid, such as water, that is highlysupersaturated with a gas such as oxygen, within a host liquid, it hasbeen found that the level of liquid flow rates that ensure laminar flowthrough small bore tubes is critical for providing bubble-free deliveryof the liquid. For example, water that is supersaturated with oxygen at1 ml O₂/g water (at standard temperature and pressure, upon release ofthe dissolved gas) can be delivered through a silica tubing 100 micronsor less in diameter within host liquids without bubble formation, forliquid flow rates of about 1 ml per minute. This flow rate allows for aflow that is laminar, and does not include any cavitation or nucleationsites for formation of bubbles. Such a system is disclosed in U.S. Pat.No. 5,569,180 to Spears. Such a system allows for the injection of theoxygen supersaturated liquid without the generation of bubbles into asystem that is sensitive to the introduction of bubbles or othernon-fully dissolved gases. Such sensitive systems include the human bodyin particular the vasculature system within the human body.

Such a system that introduces a substantially bubble-free liquid into ahost liquid, such as an intravascular space, does not permit generationof bubbles during rapid dilution (for example, less than about 2-3 barsequilibrium oxygen partial pressure upon mixing) in the host liquid. Thetubes for such systems are designed to eliminate heterogeneousnucleation sites along the inner surface of the tubes and at theproximal and distal ends of the tubes.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

According to various embodiments, a method of treating a receivingvolume of a first liquid with a transfer fluid is disclosed. A firstfluid can be pressurized with a gas to saturate or create an emulsion ofthe first fluid and the gas to form the transfer fluid. The pressure canbe at least 6 bar in a containment vessel. The transfer fluid can bereleased from the containment vessel and the released transfer fluid ispassed through a tube or series of tubes.

Various Reynolds numbers in the effluent from the tube in a range fromabout 2,220 to about 100,000 can be achieved. These Reynolds numbers canbe achieved by varying any aspect that may change the Reynolds number.Reynolds number is generally defined as a dimensionless number Re=ρvl/η,where ρ is density, v is velocity, l is length, and η is viscosity (CRCHandbook of Chemistry and Physics, 86^(th) Ed., Taylor & Francis, p.2-47, (2005)). Each of the variables can be altered by materialsselected, shape of the tube and/or outlet, etc. The released transferfluid can generate a dense population of micro-nanobubbles from the tubewith the generated Reynolds number having an average diameter that isabout 50 microns or less in the receiving volume of the first liquid.The size of the micro-nanobubbles can be altered by selecting a Reynoldsnumber and the Reynolds number can be altered by varying one of theelements of the Reynolds number calculation.

The present disclosure relates to pressurizing a liquid in the presenceof a gas to form an emulsion of liquid and dissolved gas and referred toherein as a transfer liquid or fluid. The liquid can be water, eitherpure or with contaminates. The transfer fluid can be delivered into asecond fluid at standard temperature and pressure in a manner that formsa very high density of very small bubbles of a predictable size but doesnot allow the gas to escape the second liquid quickly.

A transfer fluid is provided that may be a liquid, such as water, thatis supersaturated with oxygen or other gas for transfer of the gas to asecond volume of liquid and generation of bubbles within the secondvolume of liquid. The bubbles can be formed due to turbulence of themixing, phase change of the gas in the transfer fluid, and incipientcavitation (growth of gas nuclei and growth of nanobubbles) in thetransfer tube. Additionally, as discussed herein, the bubbles can beformed to include a diameter generally in a range of less than about 50microns. Furthermore, the bubbles can have a diameter of less than about20 microns. At least a portion of the bubbles can have a diameter lessthan 1 micron and generally in a diameter of many nanometers. Suchbubbles are referred to herein as micro-nanobubbles.

The bubbles can be used to oxygenate or transfer a selected gas to asecond body, such as a pool of water or slip stream of liquid, tooxygenate the second body. Additionally, the transfer fluid, which has aselected saturation or partial pressure of gas, can be used to transferthe gas to the second body. The small bubbles can be selected to besufficiently small to maintain the selected gas in the second bodywithout quickly or immediately rising to the surface and popping orexpanding into the atmosphere. Accordingly, the selected gas can bemaintained within the selected body for appropriate purposes.

The body can include a contaminate material or a collection ofcontaminated materials that are selected to be removed or degraded. Anappropriate enzyme, microbe or bio-nutrient can be introduced into thepool or receiving volume of fluid that uses or enhances aerobicrespiration in its lifecycle. Accordingly, a high concentration ofoxygen can be used to assist in enhancing the speed of the lifecycle andbioactivity of the microbe. The transfer fluid saturated to a selectedpoint with oxygen or air and injected into the receiving body togenerate the formation of the bubbles allows access the oxygen source bythe microbes. The microbes can then perform the breakdown or degradationof contaminate material within the receiving body for a selectedpurpose.

The transfer fluid can also be substantially pressurized with theselected gas, including air or oxygen, and exit a nozzle at a selectedvelocity and flow rate. The density of the transfer fluid exiting thenozzle can include a selected density that is substantially equivalentto a density of the transfer fluid leaving the supply vessel. Theelevated velocity exiting the nozzles can serve to introduce thelocation of bubble formation to the surface of contaminated materials.Accordingly, the pressurized transfer fluid can be used to emulsify thetransfer fluid within the receiving fluid, such as water. Thepressurized transfer fluid can be used to abrade a surface to remove amaterial from the surface. Additionally, the small bubbles can be usedto assist the abrasion or removal process by exploding on the surface toassist in removal of a selected material.

The transfer fluid can also be substantially pressurized with theselected gas, including air or oxygen, and exit a nozzle at a selectedvelocity and flow rate. The velocity and flow rate of the transfer fluidexiting the nozzle can include a selected pressure that causes themicro-nanobubbles to collapse and form a radical (which could includesuperoxide anions, peroxides, hydroxyl radicals, or hydroxyl ions) thatis introduced into a vessel to be dissolved in the transfer fluid.Accordingly, the pressurized transfer fluid can be used to chemicallyoxidize contaminates of concern and/or dissolved metals.

The system and methods disclosed herein allow for producing dense cloudsof micro-nanobubbles (bubbles that can have a population averagediameter of less than about 100 microns, less than about 50 microns, andabout 10 nanometers to about 50 microns) in an aqueous liquid thatsimultaneously do not require the use of additives, such as surfaceactive agents or ions, to achieve the bubble size and quantity and allowthe size of the majority of the bubbles to be easily adjusted from tensof nanometers to tens of microns. The bubbles can also can be deliveredinto a host liquid with a transfer liquid having a high gas: carrierliquid (v:v) ratio (e.g., greater than about 0.1:1) even for sparinglysoluble gases such as oxygen and air. The system can be easily scaled upto industrial levels, for example, 50 to many hundreds of gallons oftransfer liquid/minute for treatment of millions of gallons of hostliquids or treatment of environmental surfaces encompassing millions ofsquare meters. The bubbles can be delivered in a transfer liquid at highvelocity into water-immiscible liquids such as oils for producing fineoil-in-water and water-in-oil emulsions. The system can be used forvarious purposes, including wastewater and environmental contaminatetreatment.

According to various embodiments, a very practical and versatile way fordelivering micro-nanobubbles at high gas densities and velocities isdisclosed. The potential applications of the invention are numerous andinclude treatment of wastewater containing a wide spectrum ofcontaminants from any source, including domestic, municipal, industrial,and agricultural origins. Treatment/aeration of any water, whetherstatic or moving, contained or open, including ponds, lakes, bays,wetlands, marshes, estuaries, swamps, and oceans; brooks, streams, andrivers; and groundwater, well water, aquifers, and water in otherconfinements such as ballast tanks and storage tanks. Treatment of oilspills, including crude oil in or on any type of water or seawater inany open or contained location. Emulsification of water-immiscibleliquids, such as oils, including crude oil and fuels, such as dieselfuel. Cleaning of any surface coated with water-immiscible liquids suchas crude oil, including inanimate objects such as rocks, sand, coral,boats and other man-made objects; and animate objects including plantsand animals.

Another aspect of the disclosed tube and/or nozzle design is that anadjustment of various parameters that affect a Reynolds number of flowthrough the nozzle can be used to affect the size of themicro-nanobubbles, because all or a significant number of sites ofheterogeneous nucleation are eliminated in the nozzle design. Asdiscussed herein, various parameters can affect or change the Reynoldsnumber and these can affect the size of the micro-nanobubbles produced.The size of the micro-nanobubbles can be selected for variousapplications.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a schematic illustration of a fluid transfer system and body;

FIG. 2A is a schematic illustration of a tube according to variousembodiments;

FIG. 2A1 is an end elevational view of a tube according to variousembodiments;

FIG. 2A2 is an end elevational view of a tube according to variousembodiments;

FIG. 2B is a schematic illustration of a nozzle according to variousembodiments;

FIG. 2C is an exploded schematic view of a nozzle with a plurality oftubes;

FIG. 2D is a perspective view of a nozzle with a plurality of tubeswithin a housing;

FIG. 2E is an exemplary view of a transfer fluid being injected into avolume of water with the nozzle of FIG. 2C;

FIG. 3 is an exemplarily view of a transfer fluid being ejected at avolume of water;

FIG. 4A is an illustrative view of a container holding a first fluidthat is immiscible with a second fluid;

FIG. 4B is an illustrative view of a transfer fluid being injected intoa container holding a first fluid that is immiscible with a secondfluid;

FIG. 4C is an illustrative view of a maintained emulsion of the firstfluid and the second fluid after an injection; and

FIG. 5 is a schematic view of a flow of transfer fluid impinging upon asurface.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

With reference to FIG. 1, a gas transfer system 8 can include acontainment vessel 10 that is used to hold a transfer fluid 12 within aninternal wall 14. The containment vessel 10 can also be referred to as apressure vessel that is capped or lidded with a lid or containment top16 to seal an internal volume 18 of the containment vessel 10 defined bythe internal wall 14 and the containment top 16. The containment vessel10, however, need not have a flange lid, but can have any appropriatetop which may be welded, adhered, or otherwise enclose the internalvolume 18. The transfer volume 12 can be held within the containmentvessel 10 until it is released through a tube or passage, the tube canbe constructed as a dip tube 20 in the containment vessel. It will beunderstood, however, that the dip tube 20 withdrawal is not necessaryand a drain from the lower portion of the containment vessel 10 may beused.

The transfer fluid 12 can pass through a nozzle tube or transfer line 22and through a nozzle 24, of selected dimensions. Between the containmentvessel 10 and the nozzle 24, along the transfer line 22 can beappropriate valves, such as a first valve 26, a second valve 28, and athird valve 30. The valves 26, 28, and 30 can be appropriate valvesincluding ball valves to cease flow of the transfer fluid 12 from thecontainment vessel 10. Additionally, appropriate regulators and pressuremeters, such as a first pressure dial 32 and a second pressure dial 34can be used to monitor the pressure through the transfer line 22 of thetransfer fluid 12.

The containment vessel 10 can be pressurized with a selected gas from aselected gas source. The selected gas can be selected based on theapplication into which the transfer fluid 12 will be transferred, andcan include oxygen, helium, air, nitrogen, carbon dioxide, and otherappropriate gases. Also, the gas can be provided in a liquid form beforeintroduction into the containment vessel. Also a gas generation, such asan oxygen generation, system can be provided to provide the gas. A firstgas source can include a pressurized gas container or cylinder 40 whichcan include a regulator system including a pressure dial 42 and a firstvalve 44 that transfers a gas through a first gas transfer line 46through a second valve 48 and a second pressure dial 50 into theinternal volume 18 of the containment vessel 10.

Appropriate connections can be used to connect the gas cylinder 40 tothe containment vessel 10, such as those generally understood in theart. The gas cylinder can be a gas cylinder including those provided byAIRGAS. A second gas source can include atmospheric air that iscompressed and pumped to the containment vessel 10 with a pump orcompressor 60. A selected compressor can be a hydraulic piston pump usedto pressurize air to a selected pressure.

Within the containment vessel 10, the gas, either from the gas cylinder40, the compressor 60, or other appropriate gas source can be used toestablish the operating pressurize of the transfer fluid 12 within thecontainment vessel 10. In pressurizing the transfer fluid 12 within thecontainment vessel 10, to slightly above the established operatingpressure, a portion of the gas introduced into the containment vesselvolume 18 can become dissolved within the transfer fluid 12. The amountdissolved or concentration of the gas within the transfer fluid candepend on the solubility of the gas in the transfer fluid 12 andoperating pressure and the residence time in the pressure vessel. Thetransfer fluid can be aqueous (e.g. plain water), non-aqueous, ormixtures thereof.

The transfer fluid 12, when including an appropriate amount of dissolvedgas, can be released through the dip tube 20 and the nozzle 24 into areceiving body or volume 66. The residence time in the vessel isgenerally sufficient to fully saturate the gas in the transfer fluid 12at the selected pressure. The receiving volume 66 can be any appropriatematerial, such as water, an immiscible fluid (e.g. wastewater, processwater, vegetable or food oils, crude or natural oils, or hydrophobicmaterials). The receiving volume 66 can be held within a container 68.Alternatively, the receiving volume 66 can be a slip stream of liquid.Also, the receiving volume 66 can be an open or uncontained volume, suchas a river, stream, wetland, lake or ocean. Further, the receivingvolume 66 can be a completely or partially container portion of a largervolume of liquid, such as a boom contained in a portion of a lake orocean. For example, the nozzle 24 can be used to direct the transferfluid 12 into an open body of water, including a river, a lake, anocean, or any other appropriate volume of material. Further, asdiscussed herein, the nozzle 24 can be used to direct the transfer fluid12 to a non-liquid surface for appropriate purposes, such as abrasionfor cleaning.

As the transfer fluid 12 is removed from the containment vessel 10 andejected from the nozzle 24, make-up fluid can be introduced into thecontainment vessel 10 to reduce or eliminate the possibility of emptyingthe containment vessel 10. If the containment vessel 10 is emptied ofliquid then the gas may escape in an uncontrolled manner. The fluid maybe replenished with a replenishing fluid from an appropriate transferfluid source. It will be understood that once the containment vessel 10is empty, the gas from the gas source, including the gas cylinder 40 orthe compressor 60 will escape at an uncontrolled rate and can no longerbe efficiently transferred to the receiving volume 66 by the transferfluid 12.

According to various embodiments a recycle system 69 can transfer aportion of the receiving volume 66 through a recycle line 70 back intothe containment vessel 10. In the recycle system 69 a first pump 72 anda second pump 74 can be used to move and pressurize a portion of thereceiving volume 66 to a pressure that exceeds the selected operatingpressure in the containment vessel 10. It will be understood that anyappropriate number of pumps can be used in the recycle system 69. Thepumps can pressurize the recycled portion to a pressure greater thanthat within the containment vessel 10. Also, the recycle system cancreate a substantially closed system, but is not necessary. For example,the recycle system 69 can be used in a slip stream where the receivingvolume 66 is flowing and continually being added to and portions removedthat have been treated with the transfer fluid (e.g. a river orwastewater slip stream).

Alternatively, or in addition to the recycle system 69, a completelyseparate new fluid source 78 can be provided to replenish thecontainment vessel 10 at an appropriate rate. A third pump 80 can beused to pressurize the fluid from the new fluid source 78 before itenters the containment vessel 10. For example, the fluid from the newfluid source 78 can be pressurized to a pressure higher than that incontainment vessel 10. A valve 82 can be used to control the flow of thefluid from the new fluid source 78.

It will be understood that the refilling of the containment vessel 10with the replenishing fluid, either from the new fluid source 78 or therecycled fluid system 69 from the receiving volume 66 can equal a rateof removal of the gas transfer fluid 12 from the containment vessel 10.Thus, a selected amount of the transfer fluid 12 can be maintained inthe containment vessel 10 for dissolving the gas introduced into thecontainment vessel 10. This can allow for a continuous provision of thetransfer fluid to the receiving volume 66.

It will be understood, however, that according to various embodimentsthe second pump 74 and the third pump 80 can be combined and can be avariable speed pump. Thus, the replenishing fluid can come from multiplesources through a single pump. Also, the variable speed pump can beprovided to ensure an appropriate volume of the transfer fluid 12 in thecontainment vessel 10. That is when the transfer fluid is lower in thecontainment vessel 10 the variable speed pump can operate faster andthen slow when the volume is greater. It will be further understood,that any and all of the pumps 72, 74, and 80 can be variable speed pumpsfor the same purposes.

Regardless of the source of a replenishing liquid, the replenishingliquid can enter the containment vessel 10 through a sprayer or atomizer84. The sprayed replenishing liquid can accelerate the dissolution ofgas used to pressurize the containment vessel as the replenishing fluidresides in the containment vessel prior to exiting through the dip tube22. It will be understood that if the recycling system 69 is used,therefore, that a portion of the material in the receiving volume 66 canbe introduced into the containment vessel 10. For example, contaminatematerials, including surface active agents (surfactants), microbes,microbial nutrients, oils, can be introduced into the containment vessel10 with the recycle system 69. These contaminants have been shown toconsume additional oxygen to partially chemically oxidize somecontaminants (notably ammonia, methane, and hydrogen sulfide) within thepressure vessel without reducing the amount of oxygen delivered in thetransfer fluid 12.

The volumes of the new fluid source 78, or the gas volumes or flow ratesprovided by the gas cylinder 40 or the compressor 60 and the volume ofthe containment vessel 10 can be selected for various applications.Additionally, the flow rate of the recycle pumps 72, 74 can be selectedto provide the replenishing fluid to the containment vessel 10 at anappropriate rate. It can be selected to introduce the replenishing fluidfrom new fluid source 78 or the recycle system 69 at a selected pressureto the containment vessel 10 to assist with pressurizing the transferfluid 12 within the containment vessels 10 and overcoming the pressurefrom within the containment vessel 10.

According to various embodiments, the gas transfer system 8, discussedabove, can include a portion disclosed U.S. Pat. No. 5,569,180,incorporated herein by reference. For example, the containment vessel 10for the gas source, either from the cylinder 40 or the compressor 60 caninclude vessels as discussed above. However, to generate a transfer ofgas via a very high density of micro-nanobubbles is accomplished with atube or nozzle of an appropriate dimension (along with other factors asdiscussed herein) for generation of the micro-nanobubbles in thereceiving volume 66.

With reference to FIG. 2A, a tube 100 can be included within the nozzle24, illustrated in detail in FIG. 2B, either alone or as a bundle. Thetube 100 can be selected to include an internal diameter 102, a length104, a material to coat or form at least an interior surface 106 of thetube 100. The internal diameter 102 can be substantially uniformthroughout the length of the tube 100. A uniform internal diameter canassist in reducing nucleation points for bubble formation. The materialfor the interior wall 106 can be selected to be substantiallyhydrophilic. A substantially hydrophilic material, such as glassincluding fused silica, can assist in micro-nanobubble formation asopposed to a hydrophobic material, including fluorocarbons (e.g.TEFLON®). Hydrophobic materials produces substantially larger bubbles.

FIG. 2A1 illustrates an exemplary round or cylindrical internal diameter102 of the tube 100. The internal diameter 102 can be substantiallyconstant the length 104 of the tube 100. It will be understood thatother cross-sections or internal configurations can also be provided.For example, an elliptical or slit like opening, as illustrated in FIG.2A2, can be provided that includes a small dimension 103 and a largedimension 103 b. The small dimension 103 a and the large dimensions 103b can be substantially constant the length 104 of the tube 100, but canprovide a non-circular opening. It will be understood that otherappropriate cross-sections can include square, rectangle, oval, etc.

The micro-nanobubbles are selected to generally have a diameter of lessthan about 100 microns, and particularly less than about 50 microns, andeven further less than about 1 micron and measuring between 100 and 1000nanometers. Further, a population of the micro-nanobubbles can be formedto have an average diameter that is within the range disclosed above.The micro-nanobubbles are formed in the receiving volume 66 afterexiting the tube 100. Generally, the transfer fluid 12 will leave thetube 100 as a liquid lance that is substantially similar in diameter tothe internal diameter 102 of the tube 100. Also, the transfer fluid 12at the distal end of the tube 100 can be rapidly infused into thereceiving volume 66 causing the combined fluid to have a densitysubstantially similar to that of the non-gasenriched fluid that makes upthe transfer fluid 12.

The micro-nanobubbles can be used for various applications, as discussedfurther herein, for introducing the gas into the receiving volume 66(e.g. oxygenating the receiving volume 66). In providing the selectedinternal diameter 102 and length 104 of the tube 100 the size ofbubbles, generally in a micro-nanobubble range can be achieved.Additionally, the partial pressure of the gas within the containmentvessel 10 can be used to assist in generating the micro-nanobubbles.

Generally the internal diameter 102 can be greater than 100 microns andless than about 2.5 centimeters (about 1 inch). The length 104 of thetube 100 can be selected to be an appropriate length which can be aboutfive inches to about 15 inches, including about 5 inches, about 8inches, and about 10 inches. In addition, the internal diameter 102 ofthe tube 100 can be provided to be substantially uniform along thelength 104 of the tube 100. Accordingly, the tube 100 need not taper andcan define a substantially uniform inner cylinder within the tube 100thus having a substantially uniform cross-section throughout the length104 of the tube 100. The tube 100, therefore, is not required to includeany choke points, waists, or tapers to allow for a generation ofturbulence or nucleation points within or defined by the tube 100.

As is understood, generally in fluid dynamics, the flow of a liquidthrough a tube having particular internal dimensions and length can bedefined by a Reynolds number. The Reynolds number is also based uponvarious factors including the velocity of the fluid, the density andvelocity of the fluid flowing through the tube, and the dimensions ofthe tube. Accordingly, the flow rate and viscosity of a material, suchas the transfer fluid 12, which flows through the tube 100 can affectthe Reynolds number of the transfer fluid 12 through the tube 100. TheReynolds number can be selected to generate substantially non-laminarflow and generate the micro-nanobubbles. As is understood, laminar flowis generally deemed to be present when a calculated Reynolds number isless than about 2300. Accordingly, a Reynolds number greater than about2300 can be used to generate micro-nanobubbles.

The size and density of the micro-nanobubbles can be augmented orselected based upon the Reynolds number generated with the flow of thetransfer fluid 12 through the tube 100. The factors can includeselecting the material of at least the internal wall 106 of the tube100, the internal diameter 102 of the tube 100, and the length of thetube 104. Additionally, the partial pressure of the gas within thecontainment vessel 10 can be selected to also assist in achieving aselected Reynolds number to select the size of the micro-nanobubblesgenerated when the transfer fluid 12 flows through the tube 100.

With reference to FIG. 2B, the nozzle 24 can include a single tube 100connected to a handle/control system 110 at a selected joined area 112.The handle 110 can include a control mechanism 114 that includes anexternal handle that operates an internal valve. It will be understood,however, that the nozzle 24 can be connected to a manifold system thatallows the nozzle 24 to be operated at a distance or a plurality of thenozzles 24 interconnected together through use of a manifold system. Forexample, a plurality of the nozzles 24 can be connected to a singlesupply, in series or in parallel, and operated with a manifold to supplythe supply line. The manifold can be designed and operated in a mannerthat allows rapid decompression that causes the supplying carrier fluidto pass the high pressure end of the tube perpendicular to the tube andthereby dislodge and remove particulates that may build up on the inletend of the tube 100 during operation. The connected nozzles 24 couldthen be incorporated in other systems, such as floating boom placed inthe receiving volume 66.

With continuing reference to FIG. 2B, a plurality of the tubes 100 a,100 b, 100 c can be interconnected to provide a plurality of the tubes100 a-c in a generally parallel manner within a single one nozzle 24. Itwill be understood that any appropriate number of the tubes 100 can beinterconnected with the handle mechanism 110 to allow for the passage ofthe transfer fluid 12 through the nozzle 24. The plurality of tubes 100a-100 c, or any appropriate number less than or more than three, can beused to achieve an appropriate flow rate through the nozzle 24 that isnot necessarily achieved through a single one of the tubes 100. Forexample, if a flow rate of 66 milliliters per minute may be achievedthrough a single one of the tubes 100, but a flow rate of approximately500 milliliters per minute can be selected to flow through the singlenozzle 24. In such a situation, a plurality, such as about 8, of thetubes 100 including selected dimensions can be interconnected with thehandle mechanism 110 to assist in achieving the selected flow rate. Asdiscussed further herein, in the examples described below, including thetube 100 of various selected dimensions can achieve various selectedflow rates through the nozzle 24.

The tube 100, or the plurality of tubes 100 a-100 c, can be formed ofselected materials to assist in achieving the appropriate Reynoldsnumbers and the selected micro-nanobubble diameter through the nozzle24. For example, stainless steel, fused silica, fluorocarbons (e.g.Teflon®), polymer or plastic materials, ceramics, and the like can beselected to form the tube 100. It will also be understood, however, thatan appropriate physical characteristics of the wall 106 are selected orthat the internal wall 106 can be coated or formed of a selectedmaterial and an external surface of the tube 100 can be formed of asecond material. Accordingly, a metal or stainless steel tube can becoated with a polymer coating to achieve an internal surface of aselected material.

FIGS. 2C and 2D illustrates a nozzle 24 a, according to variousembodiments of the nozzle 24, including a plurality of tubes 100 a,according to various embodiments of the tube 100. In the nozzle 24 a,any selected number of tubes can be provided. Each of the tubes 100 a isabout 20 cm (about 8 inches) long, such as about 19.8 cm (about 7.8inches) to about 20.8 cm (about 8.2 inches) in length. The tubes have asubstantially constant internal diameter of about 0.79 mm. Each tube isformed of stainless steel.

For example, 20 of the tubes 100 a can be provided. If each tubedelivers about 0.25 gallons per minute then 20 of the tubes 100 a canprovide about five gallons per minute. Thus, the number of tubes 100 acan be selected to achieve an nozzle 24 a delivery volume rate.

The assembly of tubes 116 can be fit into a fitting 118. The array oftubes can be in a cone configuration such that an outlet end 120 a ismore disperse than an inlet end 120 b. Within the fitting 118 the tubes100 a can be sealed together so that substantially no liquid can passbetween the tubes from the fitting 118, but substantially only throughthe tubes 100 a. A cover housing 122 can be positioned over the tubeassembly 116 and mounted to the fitting 118. An outer snap ring 123 aand inner snap ring 123 b can help hold the tubes within the outerhousing 122. It will be understood that only one snap ring may be usedor that a ring with drill or throughbores may be used alternatively orin addition to the two rings 123 a, b.

As illustrated in FIGS. 2D and 2E the outer housing 122 can be held tothe fitting 118 with one or more welds 124. The welds can be spacedapart to define openings or passages 126. The passages 126 can allowliquid to flow around each of the tubes 100 a in the assembly 116. Thiscan assist in maintaining a selected bubble size from the tubes 100 a.That is, each of the tubes 100 a in the assembly 116 can actindependently to generate the selected bubble size based on thecalculated Reynolds number.

In FIG. 2E, the nozzle 24 a is positioned within the receiving volume66. That is the nozzle 24 a is submerged completely or a selected amountwithin the receiving volume 66. A supply line 128 can supply the nozzle24 a. It will be understood that a plurality of the nozzles can beconnected to the single supply line 128. Also, cleaning the inlet sideof the nozzle can be achieved by allowing the transfer fluid 12 to flowrapidly past the high pressure end of the nozzle 24 a to dislodge andcarry build-up from the inlet end of the nozzle 24 a down the supplyline 128 generally in the direction of arrow 128 a instead of forcing ittowards the nozzle 24 a.

As discussed above, the generation of micro-nanobubbles in the receivingvolume 66 by the flow of the transfer fluid 12 through the nozzle 24 canbe achieved by altering various characteristics. For example, theinternal diameter 102 and the length 104 of the tube 100 can be used toachieve appropriate Reynolds numbers. Characteristics of the tube 100,the transfer fluid 12, the gas within the transfer fluid 12, andcharacteristics of the receiving volume 66 can all be factors indetermining the size of micro-nanobubbles. For example, the internalsurface being hydrophobic (when the transfer fluid 12 is aqueous) cangenerate bubbles internally or provide nucleation points within the tube100 for the growth of bubbles within the tube 100. Hydrophilic materialsgenerally allow for less bubble formation within the tube 100.

Also, smooth surfaces on the internal surface 106 of the tube 100 canreduce nucleation points for bubble formation within the tube 100. Asmooth surface can be a surface that has values or peaks of less thanabout 50 nanometers, and further less than about 10 nanometers. Also,the end of the tube 100 can be formed or polished to be substantiallysmooth having peaks or values of less than 10-50 nanometers. Examplesinclude fused silica or polished stainless steel tubes.

Additionally, the composition of the transfer fluid 10, including thetype of fluid being aqueous fluid or non-aqueous fluids, can affect thesize of the micro-nanobubbles. In addition, suspended particles,including the size and density, can affect the bubble size generation.The velocity of the transfer fluid 12 passing through the tube 100,which can be referred to as a transit time or a tube transit time, canalso affect the number and size of the micro-nanobubbles. Accordingly, ashorter tube, such as a shorter length 104, and a higher flow rate willdecrease the tube transit time and minimize or eliminate nucleation ofbubbles within the tube 100. Additionally, the characteristics of thetransfer fluid 12 including temperature, density, and the like can alsoaffect the bubble size and Reynolds number.

Characteristics of the receiving volume 66 can also affect themicro-nanobubble size. The velocity, gas concentration, temperature,flow rate, turbulent nature of the receiving volume 66, and otherphysical characteristic of the receiving volume 66 can affect the sizeof micro-nanobubbles within the receiving volume 66. Nevertheless, giventhe characteristics of the receiving volume 66, the transfer fluid 12,and the partial pressure of the gas in the transfer fluid, the physicalcharacteristics of the tube 100 can be selected to achieve bubbles inthe micro-nanobubbles size range in the receiving volume 66.

The micro-nanobubbles can refer to a mean or average observed size ofbubbles in a cloud of micro-nanobubbles 140 formed in the receivingvolume 66. As illustrated in FIG. 3, the receiving volume can be held inthe tank 68. The cloud of micro-nanobubbles 140, as illustrated in FIG.3, is typically not visible to the naked eye and can be seen withvarious interrogation techniques, such as translumination. For example,the tank 68 can have opposed clear walls 142 and 144 and a light source146 can be directed at the cloud of micro-nanobubbles 140 through theclear walls 142, 144. Scattering of the light illustrated by hash marks148 can assist in viewing the cloud of micro-nanobubbles 140. The lightsource 148 can include an incandescent light. Also, a laser, such as anargon ion laser light, can be shown through the tank 68 and the cloud ofmicro-nanobubbles 140. The light source 146 can be used to assist in ahuman observer viewing the cloud of micro-nanobubbles 140 as a finecloud in the receiving volume 66. If the cloud of micro-nanobubbles 140is observable only with argon ion laser translumination then it isconcluded that the average bubble size in the cloud of micro-nanobubbles140 is less than or equal to about 1 micron or nanometer in size.

Generally, as discussed above, the micro-nanobubbles can be selected tobe about less than 100 nanometers (nm) to about 200 microns, includingabout 100 nm to about 100 microns, and further including less than about100 nm and less than about 50 microns. In a system where the transferfluid 12 is an aqueous fluid and the transfer fluid is saturated toabout 0.1 ml of oxygen (O₂) per gram of water to about 1.0 ml of oxygen(O₂) per gram of water, a Reynolds number of about 2,200 to about100,000 can be used to generate the micro-nanobubbles in the receivingvolume 66. The range of Reynolds numbers can further includes about5,000 to about 50,000. The pressure of the gas used to achieve thelevels of gas saturation in the containment vessel 10 can include about4 bar to about 40 bar, including about 6 bar to about 30 bar, andfurther including greater than about 8 bar, such as about 20 bar.

EXAMPLES

In the following four micro-nanobubble examples and one comparativeexample, exemplary dimensions of the tube 100 are discussed incombination with the size of bubbles generated and calculated Reynoldsnumbers related to the physical characteristics of the tube 100.

Examples Test Apparatuses

For Examples 1 and 2, a batch test apparatus was used, as illustrated inthe fluid delivery system 8 of FIG. 1, including the gas cylinder 40,the contaminant vessel 10, the nozzle 24 including a single tube ofdimensions discussed in the various examples, and the container 68including the receiving volume 66.

In particular, the containment vessel 10 included a 600 millilitercapacity 316 stainless steel Parr reactor vessel (from Parr Instruments,Inc.) that was filled with 500 milliliters of distilled water andpressurized with oxygen to a pressure of 300 psi (20 bars). Thedistilled water was then stirred at 1600 rpm with a magnetic stirrer forat least two hours to saturate the water with the oxygen at the 300 psi.A dip tube, such as the dip tube 20, was connected in the Parr reactorvessel and connected to an external delivery tube with an O-ring adapterthat allowed for a quick connection of a selected tube configuration.While releasing the distilled water from the Parr reactor vessel, acylinder filled with the oxygen (e.g. Airgas, Inc. standard Cylinder)was connected via a regulator to the Parr reactor vessel and theregulator maintained a 300 psi pressure to the Parr reactor vessel. Thenozzle was used to inject the distilled water into a glass aquariumfilled with water drawn from a tap connected to a municipal source.

Interrogation and inspection for bubbles within the aquarium includedvisual inspection by transillumination (shining a light through theaquarium tank and viewing the aquarium tank with the naked eye) withordinary light provided by an incandescent bulb and with a fiberoptically delivered beam of chemical argon ion laser radiation. Theargon ion laser radiation was from an approximately one watt sourceconnected to a silica fiber optic cable (e.g. 400 micron core) withapproximately 0.5 watts delivered to the distal end of the fiber opticcore. All of the following examples were run at a temperature of about20 degrees Celsius to about 21 degrees Celsius.

Concentration of oxygen was determined by filling a plastic syringehaving a rubber stopper plunger with about 20-30 milliliters of thesaturated water and closing one end of the syringe and tapping thesyringe. The amount of movement of the plunger within the syringe wassubtracted from the volume of original saturated water drawn into thesyringe. The difference is calculated to be a conservative estimate ofthe volume of dissolved gas in the saturated water because the liquidremains highly saturated with oxygen.

In Examples 3 and 4, a continuous flow test apparatus was used due tothe high flow rates. In particular, tap water from the same source thatfilled the aquarium tank was boosted to a pressure of about 400 psiusing a hydraulic piston pump and was delivered to a fine spray nozzle(e.g. a BETE® nozzle sold by BETE FOG NOZZLE, INC.) mounted within a 27liter 316 stainless steel pressure vessel. The pressure vessel wasinitially empty and pressurized to about 300 psi with oxygen from acompressed oxygen cylinder. Water was then sprayed into the 27 literpressure vessel from the piston pump and allowed to mix with thepressurized oxygen within the 27 liter pressure vessel. The vessel wasthen filled about half full (via measuring the weight of the vessel)with the pressurized tap water and then the saturated water was allowedto exit through the tube. A test was used to determine, as discussedabove, that the concentration of oxygen in the water was about 0.5milliliters of oxygen per milliliter of water.

Examples 1 and 2 were also re-tested using the continuous flow systemwith the 27 liter capacity pressure vessel and the source of pressurizedtap water and substantially identical results were achieved.

Example 1

Tube: Formed of fused silica and included a constant internal diameterof approximately 225 microns and a length of approximately 13centimeters (about 5 inches). The tube was used to direct the distilledwater into the aquarium tank filled with the municipal's tap water.

Reynolds number calculation: A Reynolds number of 6,075 was determinedbased on a flow rate of 66 milliliters per minute and a flow velocity of27.7 meters per second.

Bubble interrogation: incandescent light revealed no visible bubbles.Argon ion laser radiation revealed a prominent cloud of bubbles.

During the interrogation of the aquarium tank, no bubbles were viewedwith either incandescent lights or with the argon ion laser at the endof the tube within the aquarium tank. Interrogation with incandescentlight did not allow for the observation of any bubbles. However, a faintcloud of bubbles was noted with argon ion laser illumination severalcentimeters from the end of the tube. Accordingly, without being boundby the theory, it was concluded that no bubbles were generated withinthe tube and that all of the bubbles were generated due to theturbulence of the mixing of the saturated water and the tap water.Additionally, due to the apparent non-presence of bubbles under theinterrogation with incandescent lights, but due the visibility of thebubbles while in interrogation with the argon ion laser radiation, thebubbles are concluded to be the micro-nanobubble size range,particularly in the sub-micron and nanometer range.

Example 2

Tube: Formed of fused silica and included a constant internal diameterof about 450 microns and about 13 centimeters in length (about 5inches).

Reynolds number calculation: A Reynolds number of 5,670 was determinedbased on a flow rate of 100 milliliters per minute and a flow velocityof 12.6 meters per second.

Bubble interrogation: With incandescent light a fine cloud of bubblesappeared. With argon ion laser radiation a much denser fine cloud wasvisible.

Substantially no large bubbles were observed, only a fine cloud ofbubbles. Due to the visibility of both a fine cloud under incandescentlight and laser light it is predicted that the bubbles were bothnano-bubbles and micro-bubbles. In particular, the micro-bubbles beingseveral microns such as about one to 20 microns. In particular, lightmicroscopy was able to view bubbles in the 20 micron and less diameterrange. However, because the cloud appeared denser with the argon ionlaser it is predicted that the cloud included a substantialconcentration of bubbles having a diameter of less than one micron.

Example 3

Tube: Formed of stainless steel and included a substantially constantinternal diameter of about 794 microns and a length of about 20centimeters (about 8 inches).

Reynolds number calculation: A Reynolds number of 15,562 was determinedbased on a flow rate of 580 milliliters per minute and a flow velocityof 19.6 meters per second.

Bubble interrogation: With incandescent light a faint cloud of bubblesgenerally within a cone-shaped region extending from the end of the tubewas observed. The bubbles were substantially fine and an amount of largebubbles was not generally observed. With the argon ion laserillumination, the cloud appeared more dense, but still consisted of finebubbles. The observation of fine bubbles under interrogation with bothincandescent light and the argon ion laser light, with the density ofthe cloud of bubbles being viewed with the argon ion laser lightinterrogation confirmed that the bubbles were substantially within the20 micron or less range, with a greater density being in the sub-micronand nanometer range.

Example 4

The continuous flow test system was used in Example 4 with a 300 psidriving pressure.

Tube: Formed of glass including a substantially constant internaldiameter of about 1 millimeter and a length of about 13 centimeters(about 5 inches)

Reynolds number calculation: A Reynolds number of 43,300 was determinedbased on a flow rate of 2,040 milliliters per minute and a flow velocityof 43.3 meters per second.

Bubble interrogation: With incandescent light a substantially uniformand fine cloud of bubbles was observed. With argon ion laser light adenser cloud was observed.

It is concluded that the bubbles formed with the glass tube having aninternal diameter of about 1,000 microns (1 millimeter) achieved a cloudof bubbles that included micro-nanobubbles including a diameter of about15 to about 20 microns and less, with a greater density having adiameter of less than about one micron.

Comparative Example

Using the batch test system described above with the 600 milliliter Parrreactor vessel a comparative example was tested.

Tube: Formed of fused silica including 100 microns, a length of about 15centimeters (6.0 inches).

Reynolds number calculation: A Reynolds number of 760 was determinedbased on a flow rate of 3.6 milliliters per minute and a flow velocityof 7.6 meters per second.

Bubble interrogation: With incandescent light and with argon ion laserlight substantially no bubbles of any density within the aquarium tankwas observed.

It is concluded that the small diameter tube and low Reynolds numberachieved a substantially bubble-less flow of the oxygen-supersaturatedwater into the aquarium tank. Even upon exiting the tube into the tank,substantially no gas was released or no bubble nucleation occurred fromthe saturated water.

Accordingly, as illustrated in Examples 1 through 4, it can beillustrated that the size of bubbles can be controlled by using varioustube sizes and flow rates to achieve the formation of bubbles within theaquarium tank or any appropriate receiving volume 66. Further, thediameter of the bubbles can be maintained and controlled in asubstantially sub-50 micron size, including a vast majority in asub-micron and nanometer range. Accordingly, micro-nanobubbles can begenerated through a tube of selected physical dimensions to allow forthe injection of an appropriate or selected gas into the receivingvolume 66. The receiving volume 66 can be a liquid of an appropriatetype, including those discussed herein in various Applications, and canallow for transferring a gas from the saturated transfer fluid 12 to thereceiving volume 66.

Applications

There are different types of applications which may affect the optimalgeometry of a tube, as discussed herein. One application may be when thenozzle 24 or tube 100 is placed directly in the receiving volume.Another application can be when the nozzle 24 or the tube 100 is in airand ejecting the transfer fluid at a surface of the receiving volume 66.

When a distal (i.e. outlet) end of a tube is submerged under a liquid aselected design for most such applications is a circular luminalcross-section at the distal end of the tube. The velocity of thetransfer liquid upon contacting the host liquid to be treated is reducedless in comparison to other cross-sectional shapes (for a given luminalcross-sectional area) such as elliptical, slit-like, square, orrectangular. Therefore, mixing of the transfer liquid with the hostliquid is more effective, as is emulsification of water-immiscibleliquids.

When the distal end of the tube 100 is in air and only the ejectedtransfer fluid engages the receiving volume 66 then the selected designfor most such applications, primarily ones related to cleaning ofsurfaces coated with water immiscible liquids such as crude oil (inaddition to enhancing aerobic conditions during and after cleaning) canbe a slit-like luminal cross-sectional shape at the distal end of thetube 100 while maintaining the selected Reynolds number. The shape ofthe transit liquid upon exiting the tube 100 is therefore relativelywide in one dimension and can be fan-like, with the wide dimensionincreasing with distance from the end of the tube 100. The transitliquid at the distal end of the tube 100 can flow between two roughlyparallel plates, the narrow space between which can be made to beadjustable during flow, or through a fixed slit-like orifice, to producea fan-like shape of the transit liquid in air. The advantage of such ashape is that relatively large surface areas of objects to be treatedcan be treated quickly by moving the fan-like shape across the surface.The force of the tube 100 effluent per unit area of the treated surfacecan be adjusted by adjusting the distance between the end of the tube100 and the surface of the object. Of course, the force of the effluentcan also be adjusted by other factors such as the hydraulic drivingpressure at the input of the tube 100 and the width of the slit.

It will be understood that in the application where the transfer fluid24 is ejected through air that an array of the tubes 100 may alsoprovide an optimal or selected coverage. For example, the circular area,as illustrated in FIG. 2C, can provide a large surface area of contact.Also, a linear area of the tubes 100 can provide a fan shaped coveragearea. Thus, while each of the tubes can maintain an internal circularconfiguration, the output may be any selected shape.

Also, various applications can be optimized for different materials ofthe tubes 100. For example, in highly corrosive environments, like seawater (salt water), substantially non-oxidizing materials may beselected to form or coat portions of the tubes. Coatings can be appliedto stainless steel, but other metals can be used, such as titanium,tungsten, tungsten carbide, or tantalum and/or corrosive resistantalloys like Inconel® Metal Alloy (sold by HUNTINGTON ALLOYSCORPORATION), Hastelloy® (sold by HAYNES INTERNATIONAL, INC.), AndMonel® (sold by HUNTINGTON ALLOYS CORPORATION). Also, non-metalmaterials such as glass, ceramic, or polymers, can be used to eliminateor reduce corrosion.

Wastewater Treatment

As discussed above, the transferring fluid 12 can be injected into thereceiving volume 66 that is selected for various purposes. According tovarious examples, wastewater treatment can be enhanced by the additionof a gas that has been dissolved in the transfer liquid 12 and thecreation of the micro-nanobubbles in a wastewater treatment facility.The wastewater treatment can be wastewater or contaminated ambient waterthat is contained within a substantially fixed tank or pond or providedin a wastewater slip stream. The injection of the transfer fluid into atank or pond can be similar to that described above with anappropriately scaled system to provide a selected rate of injection ofthe transfer fluid 12 into the wastewater pond. The transfer fluid canalso be injected into a wastewater slip stream at an appropriatedilution, such as about 20 parts wastewater to about 1 part injectedtransfer fluid. This can produce a wastewater slip stream that is about40 parts per million injected transfer fluid, but still provide theoxygen, or other dissolved gas, at an appropriate level.

The introduction of the transfer fluid 12 into the wastewater can assistin wastewater treatment and cleaning in various manners. For example,upon collapse of the micro-nanobubbles extreme forces can be locallycreated within the wastewater or receiving volume 66. The hightemperature and pressures can generate ions or radicals, such ashydroxyl ions (—OH). The hydroxyl ions can accelerate or cause chemicaloxidation of biological materials and even inorganic materials. Suchoxidation of materials in wastewater generally makes the oxidizedmaterials less harmful to other biological life, such as humans oranimals, which later drink the water. In addition, the oxidizedmaterials can be more easily removed using various and generally knownremoval techniques.

The micro-nanobubbles can also assist in floatation of small particlesthat are present in wastewater. As discussed above, the bubbles can formin substantially small sizes to allow for connection to or adhesion tovery small particles within wastewater to allow for flotation. Themicro-nanobubbles rise very slowly through the receiving volume 66, butnevertheless rise to allow for physical extraction of solids connectedto a bubble. Further, a surfactant can either be present in thewastewater or be added to assist in the generation and density or numberof micro-nanobubbles generated through the tube 100.

Selected naturally occurring and/or proprietary microbes, enzymes and/orbio-nutrients, such as MicroSorb® microbial composition or BioNutraTech®chemical preparations sold by BioNutraTech, Inc. can be introduced intoa wastewater pond or volume to accelerate the biological degradation ofvarious contaminates in the wastewater. The rate of biodegradation istypically limited by the availability of oxygen. For example, microbescan be used to treat municipal, industrial and commercial wastewater bydigesting various contaminate chemical/biological species, including oilsuch in wastewater or contaminated water. Additionally, the contaminatedwater can include water that is simply in or near a material to beremoved, such as water in an ocean or lake that has been contaminated,at least partially, due to an oil or other chemical spill. Accordingly,contaminated water can include a selected area or volume of water thatis either contained or uncontained in a larger body of water and themicrobe can be dispersed near the contaminate.

The oxygen or gas provided from the transfer fluid 12 to the wastewaterarea can assist the microbe in the microbe's biological processes byaccelerating the biological activity, increasing the population ofcontaminate consuming microbes, and providing the physical mechanism(the emulsion) to bring the contaminate, the microbe, the nutrient, andoxygen into very close contact and thereby accelerating the entireprocess to assist in an increased rate of digestion and breakdown of thecontaminate. For example, the micro-nanobubbles can provide a largesurface area for contacting all of the elements necessary for thedegradation, including oxygen, microbe, nutrient, and contaminate. Inother words, the large number or small bubbles in the micro-nanobubblesize range allows for an appropriately sized package of oxygen for useby the selected microbes. This oxygen package also provides surface areafor all of the relevant components, e.g. microbe and contaminate, toreside during degradation of the contaminate by the microbe. The bubblecan also provide and area to contact various compounds, such as metals,for oxidation.

For example, a microbe can be positioned near the contaminate in awastewater basin and the tube 100 can be used to introduce the transferfluid 12 into the wastewater as the receiving volume 66. Themicro-nanobubbles allow for a small volume that can be biologicallyactive relative to the microbe. The microbe may phagocytize themicro-nanobubble to internalize the oxygen present within themicro-nanobubble. Additionally, the micro-nanobubble may connect to boththe microbe and a portion of the contaminate to allow for a proximity ofthe microbe, the contaminate, and a source of oxygen for aerobicrespiration of the microbe. It will be understood that additionalnutrients, such as BioNutraTech® can be added to assist in biologicalaction of the microbe in addition to the gas provided through themicro-nanobubbles.

Furthermore, other oxidizing agents can be added to assist in oxidizingwaste material and/or providing disinfection. For example, UV light canbe caused to impinge on the wastewater to disinfect treated effluentprior to discharge. A UV lamp can be provided to impinge on chemicalwastewater to provide UV radiation to chemically oxidize the constituentof concern. Various studies have shown that chemical oxidants, such ashydrogen peroxide become more cost effective when coupled with UV light.Additionally, a UV lamp can be used to impinge UV radiation on awastewater slip stream that is injected with the transfer fluid. The UVradiation can assist in oxidizing the waste material in the wastewaterto assist in the breakdown and cleaning of the wastewater. Impinging ofthe carrier fluid 12 into a wastewater pond or water volume isillustrated in FIG. 1 within the tank 68 and also in FIG. 3 whichillustrates the formation of a cloud of bubbles within a volume of waterwhich can also include waste material to be removed either viabiological degradation, oxidation, or other appropriate methods. Otheroxidizers, such as hydrogen peroxide, can be added to the wastewatereither alone or in addition to the UV radiation.

Emulsification

As illustrated in FIG. 4A, the receiving volume 66 can include a firstfluid 152 (e.g. water) may be immiscible with a second fluid 154 (e.g.oil) or may include only the second fluid 154 that is immiscible withthe transfer fluid 12. The transfer fluid 12 can be injected, asillustrated in FIG. 4B, into the substantially non-aqueous immisciblematerial, such as cooking oils (e.g. canola oil, vegetable oil, oliveoil) or other types of immiscible material including crude or refinedoil with the tube 100 that allows for generation of themicro-nanobubbles in the receiving volume 66. It will be understood thatthe tube 100 can be submerged within the receiving volume 66, accordingto various embodiments.

As illustrated in FIG. 4C, after a period of time, the emulsification ofthe aqueous transfer fluid 12 in the immiscible liquid is maintained.The mixture can include, after a period of time, regions ofsubstantially only the first fluid 150 and the second fluid 152. Inaddition, emulsification layers can include a first emulsification layer154 that includes droplets of the first fluid within the second fluidand a second emulsification layer 156 that includes droplets of thesecond fluid in the first fluid.

Emulsification examples include water that has about 50 percent oxygen(vol O₂/vol water) that is emulsified with Pennzoil® 5W-30 weightautomobile motor oil that remains substantially emulsified, where itincludes at least an emulsified portion, for at least 48 hours.Additionally, cooking oil was tested and maintained an emulsificationregion for at least about 72 hours with similarly oxygenated water.Accordingly, an emulsification of an aqueous fluid, such as water, withan immiscible liquid, such as oil, can be achieved and maintained withthe injection of the transfer fluid 12 without an addition of asurfactant.

In a particular example, the emulsification of the transfer fluid 12 andthe vegetable oil was analyzed using a Coulter N4MD submicron particlesize analyzer. The analysis indicated that submicron, including dropletsof oil within the water phase, persisted for at least about 3 days afterinjection of the transfer fluid 12 with generation of micro-nanobubblesinto the vegetable oil. Thus, an emulsification was generated andmaintained for an extended period of time without the use of anyemulsification agent or surfactant.

Additionally, perflubron (perfluorooctyl bromide) formed anemulsification upon the injection of the transfer fluid 12 (with theformation of micro-nanobubbles) that persisted for at least about 2hours. By merely shaking a 1:1 volume of the perflubron and water anemulsification lasted for less than one minute. Additionally, inspectionof the aqueous phase for particle size analysis with the Coulter N4MDsubmicron particle size analyzer indicated submicron size particles ofthe perflubron in the aqueous phase after the emulsification with theinjection of the transfer fluid 12 and the formation of themicro-nanobubbles, without any surface active agents (surfactants).

The emulsification can also assist in providing for a dispersion of thetransfer fluid and the dissolved gas into the immiscible liquid. Asdiscussed above, this can assist in wastewater treatment and treatmentof selected materials by allowing for the formation of free radicalswithin the immiscible liquids and delivery of oxygen or other gases intothe immiscible liquid that can assist in bioactivity of microbes andother compounds. For example, the transfer fluid 12 can be injected intoa waste material or contaminate (e.g. crude oil) along with the additionof microbes and an emulsion can be formed. The emulsion can allowpositioning of the micro-nanobubbles, including the selected gas (e.g.oxygen), to assist in the digestion of the waste material by themicrobes.

Surface Cleaning

With reference to FIG. 5 a stream from the nozzle 24 could be directedat a surface 200 that has been contaminated with a contaminate material202. The surface 200 can include inanimate or non-living surfacesincluding a sea wall, a boat hull, a land mass, plant life, etc.Additionally, the surface can include animate or living surfaces such asthose of animal wildlife (e.g. birds, reptiles, and mammals) and allvarieties of vegetation. As discussed above, the generation of themicro-nanobubbles with the nozzle 24 can be done with a plurality offlow rates and velocities. Thus, the force of impingement on the surface200 can be tailored for the surface 200, such as a soft and fragilesurface or a hard and sturdy surface.

In a test, eight light-colored granite rocks, 5-10 cm in diameter, werecovered with used Valvoline® high grade synthetic motor oil. The usedmotor oil could not be washed off the surface of the rocks with aconventional water jet. However, directing the transfer fluid 12consisting of water supersaturated with oxygen at 0.5 ml O₂/ml water,via an 8 in. long, 0.875 mm constant internal diameter stainless steeltube (liquid flow=600 ml/min.) in air against the rocks was successfulin removing substantially all of the visible indications of the usedmotor oil on the rock without the use or any other additives, such as adetergent. The used motor oil that was removed was observed to form anemulsion in the water, facilitating subsequent removal of the used motoroil from the surface of a plastic wash basin.

The contamination material could be oil (e.g. crude or refined oil),fuel, adhesives, etc. The nozzle 24 could be attached to a manuallyoperated mechanism, such as including a trigger 204 that could beoperated by a user 206. Alternatively, a remote manifold could be usedto allow flow of the transfer fluid through the nozzle 24 to direct thetransfer fluid 12 towards the surface 200.

Impingement of the transfer fluid 12 on the contaminate material and thesurface 200 could immediately help remove the contaminate material 202from the surface 200. Transformation of the contaminate material 202into a fine emulsion, as discussed above, along with expansion of gasfilled micro-nanobubbles within the emulsion helps to lift thecontaminate material 202 off the surface 200.

When directing the stream of the transfer fluid 12 through air thesudden impact of the stream of the transfer fluid 12 against the surface200 results in a very rapid expansion of micro-nanobubbles. The abrasiveaction of the transfer fluid 12, the explosive release ofmicro-nanobubbles, and the creation of a fine emulsion all help to cleanthe contaminate material 202 from the surface 200. The emulsificationcan include micro-nanobubbles emulsified in the contaminate material 202after impingement with the transfer fluid 12.

No surfactant is required to emulsify the contaminate material 202. Somesurfactants can be harmful to both the object to be treated and thesurrounding environment. Thus, the emulsification and removal of thecontaminate material 202 without the use of any surfactants (e.g. soapsand detergents) can assist in minimizing environmental impact inaddition to the contaminate material 202.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention. Individual elements or features ofa particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the invention, and all such modificationsare intended to be included within the scope of the invention.

What is claimed is:
 1. A method of transferring a gas, comprising:saturating a transfer liquid with a gas; transferring the saturatedtransfer liquid to a receiving liquid; and generating bubbles in thereceiving liquid having a diameter of less than about 50 microns duringthe transferring the saturated transfer liquid to the receiving liquid.2. The method of claim 1, wherein transferring the saturated transferliquid to the receiving liquid includes passing the saturated transferliquid through a transfer tube.
 3. The method of claim 1, whereingenerating bubbles in the receiving liquid includes: incipientcavitation in the transfer tube; and transfer of the generated bubblesinto the receiving liquid from the transfer tube.
 4. The method of claim1, wherein the transfer tube is formed of a fused silica; wherein thebubbles have a diameter of less than about 20 microns.
 5. The method ofclaim 2, wherein transferring the saturated transfer liquid to areceiving liquid includes transferring the saturated transfer liquidthrough the transfer tube at a Reynolds number of about 5,000 to about15,000.
 6. The method of claim 1, wherein the gas is oxygen.
 7. A systemfor transferring a gas with a transfer liquid to a receiving liquid,comprising: an elongated tube having an internal bore with asubstantially uniform internal dimension along a length of the elongatedtube from a proximal end to a distal end; and a transfer liquid sourceoperably connected to the proximal end of the elongated tube, whereinthe transfer liquid fluid source is at an elevated pressure above anambient pressure; wherein the distal end of the elongated tube isconfigured for delivering the transfer liquid into the receiving liquidthat is at the ambient pressure; and wherein the transfer liquid is gasenriched and when transferred to the receiving liquid forms bubbles thathave a diameter of less than about 50 microns within the second liquid.8. The system of claim 7, wherein the elongated tube is formed of amaterial selected from a group consisting essentially of fused silica,glass, ceramic, and polymers.
 9. The system of claim 7, wherein theelongated tube is formed of metal.
 10. The system of claim 9, wherein aninternal wall that forms the internal bore of the elongated tube iscoated with a non-oxidizing material.
 11. The system of claim 7, whereinthe substantially uniform internal dimension of the internal boreincludes an internal diameter of about 100 microns to about 2.5centimeters.
 12. The system of claim 11, wherein the internal diameteris about 0.2 millimeters to about 0.8 millimeters.
 13. The system ofclaim 7, wherein the elongated tube includes two roughly parallel platesat the distal end through which the transfer liquid flows.
 14. Thesystem of claim 7, wherein the elongated tube includes a fixed slit-likeorifice at the distal end through which the transfer liquid flows. 15.The system of claim 7, wherein the transfer liquid source includes: avessel configured to be pressurized to the elevated pressure; and aspray system to spray an aqueous liquid into the vessel to create thetransfer liquid within the vessel.
 16. A system for transferring a gaswith a transfer liquid to a receiving liquid, comprising: a plurality ofelongated tubes, wherein each elongated tube of the plurality ofelongated tubes has an internal bore with a substantially uniforminternal dimension along a length of each elongated tube from a proximalend to a distal end; a first fitting operably holding the plurality ofelongated tubes near the proximal end of each elongated tube; a secondfitting operably holding the plurality of elongated tubes near thedistal end of each elongated tube; and a transfer liquid source operablyconnected to the fitting; wherein the plurality of tubes are radiallyspaced apart a greater distance at the second fitting than at the firstfitting; wherein the transfer liquid fluid source is at an elevatedpressure above an ambient pressure and the first fitting is configuredto assist in the transfer liquid flowing through the plurality ofelongated tubes; wherein the plurality of elongated tubes are configuredfor delivering the transfer liquid into the receiving liquid that is atthe ambient pressure; and wherein the transfer liquid is gas enrichedand when transferred to the receiving liquid forms bubbles that have adiameter of less than about 50 microns within the second liquid.
 17. Thesystem of claim 16, further comprising: a housing fixed to the firstfitting and extending over the plurality of elongated tubes; wherein thehousing extends from less than an entire length of the plurality ofelongated tubes.
 18. The system of claim 17, wherein the housing isradially spaced from the first fitting to form a passage between thefirst fitting and the housing such that a portion of the receivingliquid may flow through the passage.
 19. The system of claim 17, whereineach elongated tube of the plurality of elongated tubes has the internalbore with the substantially uniform internal dimension that is about 0.1millimeters to about 0.9 millimeters.
 20. The system of claim 19,wherein the transfer liquid source is configured to transfer thetransfer fluid through the plurality of elongated tubes at a Reynoldsnumber of about 5,000 to about 15,000.